Medium severity · published Dec 2, 2025
CVE-2025-13870
Unauthorized access and subscription vulnerability in Boards
4.3
CVSS
0.2%
EPSS
No
On KEV
Description
Mattermost versions 10.11.x <= 10.11.4, 10.5.x <= 10.5.12 fail to validate the user permission when accessing the files and subscribing to the block in Boards, which allows an authenticated user to access other board files and was able to subscribe to the block from other boards that the user does not have access to
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 13% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MA
Mattermost · Mattermost
10.11.0 through 10.11.4; 10.5.0 through 10.5.12 · source: vendor
MS
Mattermost Server · Mattermost
10.5.0 before 10.5.13; 10.11.0 before 10.11.5 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-13870
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-13870
Vendor Advisory
https://mattermost.com/security-updates
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